Fluid guide plunger system

ABSTRACT

A fluid guide plunger system for a pumping mechanism for fluids comprising means to guide and constrain the plunger from radial movement as it moves through the packing element in the cylinder and a floating connection between the plunger and its corresponding power source to provide a solid connection for the high load pushing-discharge stroke, a moderate spring loading connection for the pulling suction stroke, and only minor restraint for limited radial movement of the plunger, permitting the plunger to seek its natural packing element center, thus giving longer packing life, and to adjust for misalignment possible within the pumping mechanism.

tlnrte States Patet 11 1 1111 3,891,356 Christ June 24, 1975 l54l GUIDE PLUNGER SYSTEM FOREIGN PATENTS OR APPLICATIONS [75] Inventor: Frederick Christ Long B99011 1217.072 12/1959 Germany 417/437 Calif.

[73] Assignee; Armco Steel Corporation, Primary E.\'aminerWilliam L. Freeh Middletown, Ohio Assistant Examiner-O. T. Sessions Attorney, Agent, or Firm Melville, Strasser, Foster & [22] F1led: NOV. 21, 1973 Hoffman [21] Appl. No: 417941 [57] ABSTRACT [52] [1.8. CI 417/437; 92/168 A fluid guide plunger system for a pumping mecha- [51] Int. Cl. F04b 19/22 nism for fluids comprising means to guide and con- [58] Field of Search 417/437, 539, 319; 92/165 strain the plunger from radial movement as it moves 92/166 through the packing element in the cylinder and a floating connection between the plunger and its corre- [56] References Cited sponding power source to provide a solid connection UNITED STATES PATENTS for the high load pushing-discharge stroke, a moderate j 092 641 9/1927 Dorm 417/539 spring loading connection for the pulling suction 56 4 8/1962 16 stroke, and only minor restraint for limited radial 3114.326 12/1963 Yaindl 137/4544 mOVemeHI 9f the Plunger, Permitting the Plunger to 3,276,390 10/19 6 Bl d ff Qt 1 417/319 seek its natural packing element center. thus giving -3427.988 2/1969 Redman et a1 1 417/569 longer packing life, and to adjust for misalignment 3.602.613 8/1971 Gunther et a1 v 1 417/437 possible within the pumping mechanism 3.749529 7/1973 Cornelsen 417/437 3.2120922 6/1974 Buse et 111. 1, 417/539 7 Clams 2 Drawmg Flgures 1 1 A V s \13 or: Z2 Z4 52 Z8 46 46 5G 5 54 ,5 m

PATENTEI] JUN 2 4 I975 SHEET FLUID GUIDE PLUNGER SYSTEM BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to improvements in pumps of the plunger type employed in connection with rotary drilling and production of wells, and in particular, to improvements with respect to plunger misalignment problems and the like.

2. Description of the Prior Art The prior art has long been concerned with misalignment of pump plungers. However, most packing ele ment systems in prior art pump cylinders provide only structural parts to restrain the packing from extruding, but not to guide the plunger. The packing must adjust for misalignment of the plunger which could decrease its life. Some plungers are connected to their corresponding power sources by flexible members, such as fluid seal mandrels, in order to reduce misalignment loads; however, most plungers are connected to the corresponding power sources by rigid clamps or the like. Some prior art pumps have utilized a method of achieving plunger alignment by relying entirely on presure from the charging pump to maintain contact between the plunger and a crosshead rod joining the plunger and its corresponding power source.

While such prior art arrangements have proven to be satisfactory in some respects, they have also proven to have major limitations and short comings.

SUMMARY OF THE INVENTION The present invention provides an improved fluid guide plunger system to guide and constrain the plunger from radial movement as it moves through the packing element in its cylinder and a floating connection between the plunger and its respective power source to provide a solid connection for the high load pushing-discharge stroke, a moderate spring loading connection for the pulling-suction stroke, and only minor restraint for the limited radial movement of the plunger, permitting the plunger to seek its natural packing element center, thus giving longer packing life, and to adjust for misalignment possible within the pumping mechanism.

Briefly, the means to guide and constrain the plunger from radial movement as it moves through the packing element in its cylinder comprises a substantial guide bushing on at least one side of the packing element. The cylinder, guides and plunger are closely fit to permit free axial movement of the plunger while limiting the radial movement thereof.

The floating connection comprises a hollow housing with openings at its forward and rearward ends. The housing is provided with an annular interior groove sized to just nicely receive the end of a power member associated with the power source. Means are provided to secure the end of the power member to the housing. The opening of the forward end of the housing is defined by an annular rim. The plunger has a disc or washer secured to it by suitable screw means. The disc or washer is adapted to be received within the housing and to be maintained in abutment with the forward end of the power member. Spring means abuts the forward end of the disc or washer and the annular rim to maintain the disc or washer in abutment with the power member.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary, longitudinal, cross sectional view of a pump showing the improved fluid guide plunger system of the present invention.

FIG. 2 is an enlarged fragmentary, longitudinal, cross sectional view of the pump shwon in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A typical pump or pumping mechanism 10, which may be employed in but which is not necessarily limited to the drilling and production operations of oil and water wells, is disclosed in FIG. I. As can be seen, the

pump 10 is provided with a pump body 12 (the powerend of the pump), a fluid end 14 provided with an inlet connection 16, communicating with a well or any suitable supply reservoir, and an outlet passage (not shown), communicating with any desired vessel or the like. Valve seats 20 and 22 are provided between intake connection 16 and the fluid end plunger cavity 15, and between the fluid end plunger cavity 15 and the transverse outlet passage (not shown), respectively. Intake and outlet valves, such as the spring loaded check valves 24 and 26, control the flow of fluid from the intake connection 16, into the fluid end plunger cavity 15, and through the outlet passage. The plunger cylinder 28 and its assembly is fixedly attached to the fluid end 14 by means of the bracket or bushing 32, which comprises the receptacle therefor. Static sealing between high pressure fluid and the atmosphere is accomplished by metal-to-metal joints backed by suitable seal or elastomer elements 34.

A plunger 36 is axially mounted within the cylinder 28 and movable therein between an extended position, as shown in FIG. 1, and a retracted position. Movement of the plunger 36 is accomplished by joining the plunger through coupling means 40 to any desired power source (not shown) having an associated power member 42. As will be more fully described hereinafter, the coupling means 40 of the present invention comprises a floating connection.

As can be seen, a suitable packing element 44, such as spring loaded Vee packing or non-adjustable packing, along with the retaining nut or cap 46 and a substantial guide bushing 48 or 50 on at least one side of the packing element 44, secure the components of the plunger assembly in the cylinder housing 28. It will of course, be understood that if only one substantiai guide bushing is utilized on one side of the packing element 44, a suitable retainer or the like is positioned on the other side of the packing element.

According to the present invention, the substantial bushings 48 and 50 on either side of the packing element 44 guide and constrain the plunger 36 from radial movement it moves through the packing element 44 in the cylinder 28. As can be seen, the cylinder 28, the guides 48 and 50 and the plunger 36 are closely fit to permit free axial movement of the plunger 36 while limiting the radial movement thereof.

Lubricant and coolant may be fed to the plunger 36 through the cylinder housing holes and the guide holes 52 and 54, respectively, reducing friction and heat on the packing element 44.

The coupling means 40 of the present invention comprises a floating connection. This connection includes a two-piece, split clamp housing 56 with openings at the forward and rearward ends 560 and 56b, respectively, thereof. The housing 56 is provided with an annular interior groove 58 sized to just nicely receive the enlarged end 42a of the power member 42. The enlarged end 42a of the power member has a transverse perforation 60 and each of the pieces of the housing 56 have a corresponding perforation 62, so that when the perforations 60 and 62 are in axial alignment bolt means, such as the bolt 64 and the nut 66, may be placed through the enlarged end 42a of the power member 40 and the housing 56 to hold the assembly together.

The opening at the forward end 5641 of the housing 56 is defined by an annular rim 68. The plunger 36 has a washer or disc 72 secured to it by a suitable screw 74. The washer or disc 72 is adapted to be received within the housing 56 and to be maintained in abutment with the forward end 42a of the power member 42. Spring means 76 abutting the forward end 72a of the washer and the annular rim 68 maintain the disc or washer 72 in abutment with the power member 42.

In same instances an existing or conventional clamp 56 may be converted to a floating connection by use of a suitable adopter ring or the like which fits within the annular interior groove 58 adjacent the annular rim 68.

In practice the screw 74 joining the disc or washer 72 to the end of the plunger 36 is sized to break in the event of seizure of the plunger.

The spring means 76 may comprise any suitable spring or the like. However, in practice it has been found that a conical spring or belleville washer is preferable.

In operation, when the plunger 36 moves from its extended or discharge position, as shown in FIG. 1, to its retracted or back stroke position, the reduction or pressure within the fluid end plunger cavity causes the intake valve 24 to open and fluid is drawn through the intake connection 16 into the fluid end plunger cavity l5 and into the cylinder 28. When the plunger 36 moves from its retracted or back stroke position, to its extended or discharge position, as shown in FIG. 1, it pushes against the fluid within the cylinder 28 and the fluid end plunger cavity 15, causing the intake valve 24 to close and the outlet valve 26 to open. The fluid is then discharged through the outlet passage. During operation, the guide bushings 48 and 50 permit free axial movement of the plunger 36 while limiting the radial movement thereof. The floating connection of the coupling means 40 provides a solid connection for the high load pushing-discharge stroke, a moderate spring loading connection for the pulling-suction-stroke, and only minor restraint for limited radial movement of the plunger 36, thus permitting the plunger 36 to seek its natural center of the packing element 44, making possible longer runs before the plunger and packing must be replaced, and to adjust for misalignment possible within the pump 10.

While certain preferred embodiments of the invention have been specifically illustrated and described, it is understood that the invention is not limited thereto, as many variations will be apparent to those skilled in the art, and the invention is to be given its broadest interpretation within the terms of the following claims I claim:

1. A pumping mechanism for pumping fluids having a fluid end containing an intake and an outlet provided with an intake valve and an outlet valve, respectively,

at least one cylinder communicating with said fluid end, said cylinder having a packing element, a plunger axially mounted within said cylinder and movable therein in an extended position and in a retracted position, a power source including an associated power member. and coupling means joining said plunger and said power member, said pump pulling fluid through said intake valve into said fluid end and said cylinder when said plunger moves from its extended position to its retracted position and discharging fluid through said outlet valve when said plunger moves from its retracted position to its extended position; characterized by said coupling means being a floating connection comprising a hollow housing with openings at the forward and rearward ends thereof, said housing having an annular interior groove sized to just nicely receive the end of said power member, means securing the end of said power member in said housing, the opening of the forward end of said housing being defined by an annular rim, a disc secured to one end of said plunger by screw means, said disc being adapted to be received within said hous ing and maintained in abutment with the forward end of said power member, and spring means abutting the forward end of said disc and said annular rim to maintain said disc in abutment with said power member, whereby said floating connection provides a solid connection for the high load pushing-discharge stroke of said plunger, a moderate spring loading connection for the pulling-suction stroke of said plunger, and only minor restraint for limited radial movement, permitting said plunger to seek its natural packing element center, thus giving longer plunger and packing element life and adjusting for misalignment possible within said pumping mechanism.

2. The pumping mechanism according to claim 1, wherein means are provided to guide and constrain said plunger from radial movement as it moves through said packing element in said cylinder to minimize packing wear, said guide and constraining means comprising a substantial guide bushing adjacent said packing element, said cylinder, guide bushing and plunger being closely fit to permit free axial movement of said plunger while limiting the radial movement thereof.

3. The pumping mechanism according to claim 2, wherein a substantial guide bushing is located on each side of said packing element.

4. The pumping mechanism according to claim 1, wherein said housing is of the two-piece, split clamp type.

5. The pumping mechanism according to claim 1, wherein said screw means securing said disc to the end of said plunger is sized to break in the event of plunger seizure.

6. The pumping mechanism according to claim 1, wherein the forward end of said power member is provided with a transverse perforation and said housing is provided with a corresponding perforation, and said means for securing the forward end of said power member to said housing comprises bolt means placed through said perforations in said power member and said housing when said perforations are in axial alignment to hold said assembly together.

7. The pumping mechanism according to claim 2, wherein means are provided for conducting lubrication to said guide bushings. 

1. A pumping mechanism for pumping fluids having a fluid end containing an intake and an outlet provided with an intake valve and an outlet valve, respectively, at least one cylinder communicating with said fluid end, said cylinder having a packing element, a plunger axially mounted within said cylinder and movable therein in an extended position and in a retracted position, a power source including an associated power member, and coupling means joining said plunger and said power member, said pump pulling fluid through said intake valve into said fluid end and said cylinder when said plunger moves from its extended position to its retracted position and discharging fluid through said outlet valve when said plunger moves from its retracted position to its extended position; characterized by said coupling means being a floating connection comprising a hollow housing with openings at the forward and rearWard ends thereof, said housing having an annular interior groove sized to just nicely receive the end of said power member, means securing the end of said power member in said housing, the opening of the forward end of said housing being defined by an annular rim, a disc secured to one end of said plunger by screw means, said disc being adapted to be received within said housing and maintained in abutment with the forward end of said power member, and spring means abutting the forward end of said disc and said annular rim to maintain said disc in abutment with said power member, whereby said floating connection provides a solid connection for the high load pushing-discharge stroke of said plunger, a moderate spring loading connection for the pulling-suction stroke of said plunger, and only minor restraint for limited radial movement, permitting said plunger to seek its natural packing element center, thus giving longer plunger and packing element life and adjusting for misalignment possible within said pumping mechanism.
 2. The pumping mechanism according to claim 1, wherein means are provided to guide and constrain said plunger from radial movement as it moves through said packing element in said cylinder to minimize packing wear, said guide and constraining means comprising a substantial guide bushing adjacent said packing element, said cylinder, guide bushing and plunger being closely fit to permit free axial movement of said plunger while limiting the radial movement thereof.
 3. The pumping mechanism according to claim 2, wherein a substantial guide bushing is located on each side of said packing element.
 4. The pumping mechanism according to claim 1, wherein said housing is of the two-piece, split clamp type.
 5. The pumping mechanism according to claim 1, wherein said screw means securing said disc to the end of said plunger is sized to break in the event of plunger seizure.
 6. The pumping mechanism according to claim 1, wherein the forward end of said power member is provided with a transverse perforation and said housing is provided with a corresponding perforation, and said means for securing the forward end of said power member to said housing comprises bolt means placed through said perforations in said power member and said housing when said perforations are in axial alignment to hold said assembly together.
 7. The pumping mechanism according to claim 2, wherein means are provided for conducting lubrication to said guide bushings. 